Below is a list of Rodless Cylinders manufacturers from Portland, Oregon. Rodless cylinders are pneumatic tools that use the force of compressed air to move a piston. Unlike many air cylinder varieties, many of which feature pistons attached to rods of varying dimensions, rodless cylinders feature pistons that are not connected to rods. The reasons for employing rodless cylinders vary depending on context. Rodless cylinders are prized because they use less space than do cylinders that use rods.